Cholesterol Levels: Everything You Need to Know
Cholesterol is a fat-like substance found in the blood and in all cells in the human body. The liver synthesizes the required amount of this substance, however, the high cholesterol levels are related to the onset of various diseases.
The functions of cholesterol within the body are very diverse. It’s part of the membrane of every cell in the human body, and provides fluidity and permeability. It’s also the precursor for certain substances such as adrenal gland steroid hormones, bile, and vitamin D.
Having high levels of cholesterol in the blood is a very common health problem today. In fact, studies show that up to 45% of people in any given population have high cholesterol levels.
How is cholesterol found in the blood?
The measurement is done through a blood test called a lipoprotein panel, which determines the levels of the substance and other lipids in the blood. Cholesterol is transported in the blood bound to certain proteins, so it’s possible to find high-density lipoproteins (HDL) and low-density lipoproteins (LDL).
LDL is known by many people as the “bad cholesterol”, as it’s the one that tends to accumulate in the tissues and cause different conditions. Triglycerides are not a type of cholesterol per se, however, if they occur in excess, then they can cause damage. They’re also measured in the same test in the form of very-low-density lipoprotein (VLDL).
On the other hand, HDL can be identified as “good cholesterol”, as its functions include facilitating the metabolism and elimination of LDL and VLDL. The levels of all these compounds can be measured by a cholesterol test, which determines if there’s any alteration in their levels.
A laboratory test can also measure total cholesterol in the blood, which would be the sum of all the compounds described. In addition, it’s also possible to count non-HDL cholesterol, that is, the total amount of LDL and VLDL in the blood.
What are normal cholesterol levels?
Normal cholesterol and triglyceride levels can vary depending on the sex and age of each person, however, they must be within a pre-established range. It’s also important to note that the concentration of these fatty compounds is measured in a unit called milligrams per deciliter.
Generally speaking, people under the age of 19 have lower cholesterol levels than older people. This is a physiological condition and levels tend to decrease over the years. In this sense, the normal levels for a person under 19 years of age are the following (expressed in milligrams/deciliter):
- Total cholesterol: less than 170
- Non-HDL: less than 120
- HDL: greater than 45
- LDL: less than 100
The variation in people over 20 years of age is not so remarkable. However, it’s necessary to take into account that these values increase. Total cholesterol levels can reach up to 200 in these patients, which is within normal values.
Experts state deem total cholesterol to be high when its concentration exceeds 240, while levels between 200 and 239 are taken as a warning. On the other hand, low levels of LDL and high levels of HDL are good for health in most cases.
Why do cholesterol levels rise?
As previously mentioned, the human body synthesizes all the necessary cholesterol through a set of enzymes in the liver. However, some foods such as meat and eggs have high concentrations of this compound and can alter the levels.
Having high blood cholesterol levels is a medical condition known as hypercholesterolemia, which can be caused by multiple conditions. Among the risk factors for this condition are a sedentary lifestyle, smoking, obesity, and diabetes.
On the other hand, having a poor diet is one of the main factors that increase cholesterol levels. Unbalanced diets affect the body in all areas, so eating foods rich in saturated fat increases the concentration of LDL and VLDL in the blood in a very short time.
Hypercholesterolemia can also be due to a genetic alteration, in fact, studies show that it’s due to an alteration in the short arm of chromosome 19. This disease is characterized by high levels of LDL and a risk of developing heart disease at an early age.
What are the risks?
Having cholesterol levels above normal values represents a great health risk, as it increases the probability of developing heart and metabolic diseases. One of the main risks is the development of atherosclerosis and coronary heart disease.
In both diseases, there’s an accumulation of fat on the walls of the blood vessels, forming a plaque, which reduces the vascular lumen and reduces the supply of oxygen to the tissues. These fatty plaques called atheromas can be located in any blood vessel and cause multiple conditions.
When atheromas are in the coronary arteries, they can cause an acute myocardial infarction (AMI). Fatty plaques can also be located in the brain, increasing the likelihood of having a stroke.
Another common problem triggered by atheroma plaques in the blood vessels is angina pectoris. This is nothing more than an oppressive pain located in the precordial area, just above the heart, which appears when the heart muscle doesn’t have a sufficient supply of oxygen at a certain time.
How to lower cholesterol levels?
Fortunately, it only takes a few lifestyle changes to lower blood cholesterol levels. Some research shows that one of the most effective methods is to modify the diet, decreasing the consumption of saturated fat, and increasing the fiber intake.
The consumption of fruits and vegetables also helps to return the cholesterol to normal values. It’s also necessary to avoid frying food and opt for grilling or steaming. Exercising, reducing stress and smoking, and increasing your water intake are helpful measures.
In general terms, a change in lifestyle is recommended, and efforts should be made to eliminate a sedentary lifestyle almost entirely. Unfortunately, there are cases where these changes don’t have any effect, and so cholesterol medications must be used, statins being one of the most useful compounds.
Constant check-ups are essential
Blood cholesterol levels can rise without giving any clear sign of it. In this sense, constant medical check-ups are of vital importance in order to prevent the appearance of atherosclerosis or other pathologies associated with hypercholesterolemia.
Everyone under 45 should have a lipid panel at least every 5 years. However, older adults should have this test every 2 years, as the probability of suffering changes during this period of life is greater.
Lifestyle and diet changes are often more than enough to return cholesterol levels to normal. However, it’s always advisable to consult the doctor before making any decisions. Only they will be able to evaluate the general condition of the patient and decide the best therapy to follow.
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